Diagnostic cytology, particularly in the area of clinical pathology, bases diagnoses on a microscopic examination of cells and other biological samples. The accuracy of a diagnosis and the preparation of optimally interpretable specimen slides may depend both upon adequate patient sampling and on culture or slide preparation procedures.
Prompt processing of urine to obtain fresh cells traditionally has been recommended to ensure the accuracy of quantitative culture results, urinalysis and microscopy. Fresh cells tend to stick to a glass slide much better than cells from preserved urine, allowing for smoother cell spread onto the glass body. Delays in processing, negligent care in either inpatient or outpatient settings and lack of refrigeration may lead to non-optimal slide preparation. One known solution to the delay problem is the use of chemical preservatives with the urine. The presence of liquid preservatives, however, in the urine specimen raises the specific gravity of the specimen to unmeasurable levels and may limit the potential usefulness of the urine for various types of traditional quantitative analysis, such as slide microscopy.
A number of urine or other biological fluid specimen containers have been developed to allow liquid biological specimens to be tested without removing the lid of the urine or biological fluid container.
U.S. Pat. No. 2,953,132 discloses a parenteral solution bottle with an inwardly projecting tube and a rubber stopper and an associated dispenser bottle which is adapted to introduce medication into the parenteral solution bottle.
U.S. Pat. No. 3,066,671 discloses a disposable additive container provided with a cover formed with a shaft guiding sleeve. The shaft guiding sleeve receives an infusion holder and an additive container.
U.S. Pat. No. 3,608,550 discloses a transfer needle assembly for transferring fluid from a fluid source to a fluid collection container. The needle assembly includes a first cannula mounted on a support means which engages the collection container and is adapted to be connected at its forward end to the fluid source and at its rear end to the collection container. A second cannula is mounted on the support means and is adapted to be connected at its forward end to the fluid source and at its rear end to the atmosphere allowing fluid to be transferred from a fluid source to a collection container by atmospheric pressure when the volume within the collection container is sufficiently increased.
U.S. Pat. No. 3,904,482 discloses an apparatus and method for the collection, cultivation and identification of microorganisms obtained from bodily fluids. The apparatus includes an evacuated tube containing a culture medium, an inert gaseous atmosphere and a vent-cap assembly. The tube containing the culture medium is fitted with a stopper for introduction of bodily fluid by means of a cannula and, after growth of the organisms, transfer of the cultured medium is completed for subculturing or identification procedures.
U.S. Pat. No. 4,024,857 discloses a micro device for collecting blood from an individual or other blood source into a sampler cup. The cup has a removable vented truncated cone-shaped top with a capillary tube passing through a well formed in the top, proximate to the inside wall of the cup to deliver blood directly from the blood source to the cup.
U.S. Pat. No. 4,116,066 discloses a device for the collection of a liquid, such as urine, comprising an open ended urine collection container provided with a hollow cannula attached to its bottom. The cannula is slotted near its base, and serves as the conduit through which liquid may be transferred from the container to an evacuated tube. When the stopper of the evacuated tube is punctured by the cannula, the pressure differential causes liquid deposited in the container to be drawn through the slot into the hollow cannula and into the tube.
U.S. Pat. No. 4,300,404 describes a container which has a snap tight lid. The lid is provided with a cannula which extends into the lower end of the container and projects through the lid at its upper end so as to be able to pierce the stopper of an air-evacuated tubular container. The container is also provided with a depressed bottom to assure the maximum collection of fluids. The lid is provided with a recess to accommodate the air-evacuated tube.
None of the previously noted references solves the problem of transferring cells in a uniform layer to a slide for examination while at the same time preserving the fluid from which the cells were taken.
It should be noted that the process of transferring or collecting cells onto a slide or membrane is generally carried out by preserving or fixing the cytology specimen in the body fluid, secretions or smears.
Currently, body fluid samples are collected for cytological examinations using special containers. These containers usually contain a preservative solution for preserving the cytology specimen during shipment from the collection site to the cytology laboratory. Furthermore, cytology specimens collected from the body cavities using a swab, smear, flush or brush are also preserved in special containers with fixatives prior to transferring cells onto the slide or membrane for staining or examination. Desirable fixatives are alcohol and acetone fixatives.
The recovery (yield) as well as the quality of the cytology preparations from fresh body fluid specimens is superior as compared to routine cytology preparations requiring the use of preservatives. This is likely due to the fact that fresh cells stick better to glass and/or membranes than those preserved in alcohol or other preservatives.